Linear friction welding (LFW) is a process of joining two components which may be made from the same or different materials. The LFW process typically involves pressing the two components together under a large amount of force and rapidly vibrating the components with respect to one another to generate friction at the interface between the two components. The pressure and movement generate sufficient heat to cause the material at the interface to plasticize. Once the material at the interface begins to plasticize, the vibration is stopped and an increased force is applied. As the plasticized material of both components cools in this static condition, the components are bonded together and a weld is formed. While LFW is suitable in many applications, heretofore, LFW has not been practical for repair welds.
In certain embodiments, the linear friction welding (LFW) apparatus of this invention includes two vibrating assemblies, which simultaneously vibrate both work pieces along different weld axis within the plane of the weld interface during the weld process. The LFW apparatus allows both work pieces to be independently vibrated against one another along different weld axis to control and concentrate the application of thermal energy across the weld surfaces caused by friction in certain areas of the weld surface and during certain times during the weld process. Each vibrating assembly independently controls the amplitude and frequency of the vibration of its work piece relative to the other during the weld process, and also allows the vibration to instantly stop with no load on the work piece. In other embodiments, the linear friction welding (LFW) apparatus of this invention uses a vibrating assembly that moves one of the work pieces along a fixed orbit within the plane of the weld interface during the weld process.
The apparatus and method of the present invention may take form in various systems and components, as well as the arrangement of those systems and components. The above described features and advantages, as well as others, will become more readily apparent to those of ordinary skill in the art by reference to the following detailed description and accompanying drawings. The drawings are only for purposes of illustrating exemplary embodiments and are not to be construed as limiting the invention.